New molecular spectroscopic approaches will be developed for the selective, sensitive, precise measurement of drugs (including pesticides and polycyclic aromatic hydrocarbons) in pharmaceutical products, biological materials, and other types of samples. The new approaches involve a broad range of spectroscopic methods: including laser excited luminescence, photoacoustic, and photoionization detection of analytes separated by liquid chromatography; laser excited photothermal spectroscopy of molecules in the gas, liquid, and solid phases, particularly gas chromatography, liquid chromatography, and thin layer chromatography; evaluation of aerosols as an intermediate physical state with laser excited luminescence, photoacoustic and photoionization detection; site selection luminescence spectrometry based upon 2 photon-excitation of glasses, of crystalline matrices, of species on solid substrates, and of polymer films including the benefit of fluorescence hole burning; sequential excitation of gaseous molecules with lasers and fluorescence or ionization detection for high spectral selectivity; surface-enhanced Raman spectrometry of molecules in capillaries and on fiber optics coated with metal films and in metal hydrosols; room temperature phosphorimetry including mechanistic studies, new solid substrates based on polymer films, porous vycor and chemically modified surfaces, magnetic field effects, and the complimentary nature of room temperature delayed fluorescence; luminescence of molecules in organized media, including time resolved phosphorimetry, thin films, and micro-capillary cells; synchronous luminescence including time resolved phosphorimetry, HPLC detection, and fingerprinting of samples; measurement of analytical figures of merit of drugs, pesticides and polycyclic aromatic hydrocarbons by a variety of spectroscopic methods to provide a data base; and methods based upon the use of charge coupled devices.